It's part of the reason many Hoosiers are taking extra precautions.
The Center for Disease Control and Prevention reports there have been more than 1,100 cases of the West Nile disease this year, since it was detected in the states in 1999. In Indiana, state health officials said, for 2012, they have discovered there are 67 counties with mosquitoes that carry the virus. In 2011, there were only 34 counties with mosquitoes that carry the virus.
"Overall mosquito population is low but what we don't want to hapepn is for people to become complacent because the mosquito population is low but the infection rate is high," said Terry Gallagher, Mosquito Control Supervisor.
Marion County officials said they are doing their part. There are crews who go around the city spraying Monday through Friday, investigating as well.
Crews will continue spraying until the first solid frost. Health officials said they want people to make sure they are looking around their homes, getting rid of any standing water or places where mosquitoes would breed.
"The city is doing a good job in keeping them controlled and every once in a while people come through to make sure there isn't any standing water," said Hooper.
State officials said they conduct comprehensive mosquito surveillance programs where they test and trap mosquitoes across Indiana. According to state officials, this begins in May and continues through the end of October. State officials said Marion and Allen Counties have their own trapping and testing programs through the health department, which they support.